Encouraged by the feuds of the Armenian princes, Sajid emir Yusuf ibn Abi’l Saj launched a military campaign against Armenia in 909. Catholicos Hovhannes V met emir Yusuf with gifts in an attempt to stop the advancement of the enemy. However, the Arab emir considered the gifts insufficient and imprisoned the Catholicos.
Brothers Gagik and Gurgen Artsruni, in their turn, also presented gifts to the emir and joined his campaign. Gagik Artsruni, who had a quarrel with King Smbat I over control of the city of Nakhichevan, declared Vaspurakan an independent kingdom in 908 and received a crown from Yusuf along with a promise to inherit the Armenian throne after the overthrow of Smbat.
The Arab campaign began with Syunik. Smbat instructed the defenders of the Yernjak fortress to protect his mother, wife, and brother’s family. He left Syunik together with his brother Sahak.
His other brothers Babken and Vasak along with Prince Grigor Supan were unable to resist the Arab invasion – Syunik came under the control of the Arabs and was devastated.
After the capture of Syunik, Yusuf marched towards the Ararat valley. He reached Dvin on Easter Day. The population, unaware of his advances, was slaughtered without effort. In a matter of days, life was extinguished in hundreds of houses.
In 910, in the Nig district in the town of Dzknavachar (Ձկնավաճառ), Armenian troops came out against each other – Artsruni against Bagratuni. The royal Bagratuni army was led by the sons of the king of Armenia Ashot and Mushegh. The bloody battle “Armenians against Armenians” brought defeat to the army of Bagratuni.
The betrayal of the Sevordyats regiment in the ranks of the Bagratuni army played a key role at the end of the battle. They left the battlefield, taking Ashot with them (future King Ashot II the Iron). Mushegh was captured, surrendered to Yusuf, and later beheaded on his orders.
Gagik Artsruni then received an order to capture Bagrevand. The Arab emir conquered the whole country, mainly using Armenian troops. As a result, Armenia found itself in absolute chaos.
Having conquered the whole country, Yusuf began the liquidation of the Armenian princes who had sided with him.
Dreaming of the Armenian throne, Gagik Artsruni at first was the most faithful executor of the will of Yusuf. Subsequently, horrified by the insidiousness of Yusuf, he decided to leave him together with his brother Gurgen. He secretly notified King Smbat of his plans.
King Smbat, of course, could not believe and trust the brothers-traitors. The regiments of Artsruni – or rather, their remains – retreated to Vaspurakan. Here on the island of Aghtamar, Gagik would spend years building the Surb Khach Monastery for “atonement for his sins and peace of his soul” («ի քավութիւն յուր մեղաց եւ ի հանգստութիւն յուր հոգվոյ»).
Smbat entrenched in the Kapuyt fortress in Erashadzor. He hoped that he could unite the disparate forces and ensure organized resistance to the enemy. However, all the aspirations of Smbat were doomed to failure.
Yusuf besieged the fortress and with the support of Armenian troops launched an attack. The fortress resisted for a short time. Seeing that the warring, killed, and wounded were mostly Armenians and trusting Yusuf’s promises to achieve peace through negotiations, the Armenian king left the fortress to see the Arabs.
Yusuf ordered that Smbat be shackled and imprisoned. Then, the Arabs moved to Shirakavan and headed south to capture the Yernjak fortress.
The defenders of the fortress stubbornly resisted the enemy. Yusuf ordered Smbat to be brought out under the walls of the fortress so that the Armenian king would urge the defenders of the fortress to surrender. In return, Yusuf promised Smbat freedom.
However, the Armenian king encouraged the defenders not to give up. Smbat was beheaded on the spot, thereby becoming a martyr. His body was sent to Dvin and crucified on the city walls, causing moral pain and horror in the local population.
Soon, the Yerndzhak fortress fell as well. Its defenders were murdered, while the women of the princely family were taken prisoner.
The era of anarchy began in Armenia – seven long and intense years passed in hunger and horror. Some of the Armenian princes who managed to escape from Yusuf’s captivity returned to their fortresses from where they would destroy enemy units left by Yusuf with sudden attacks. At the same time, they and their troops raided the possessions of their neighbors.
Five years after the defeat of Armenia and its plunder, Yusuf returned to Atropatene, leaving his deputies in Dvin to rule the country.
In 921, the heir to the royal throne Ashot began his struggle against the enemy. Ashot would receive the name Yerkat (Iron) for his braveness against the Arabs. He managed to subjugate the rebellious princes and after a stubborn struggle drive the Arabs out of Armenia.
In 922, Caliph Jafar al-Muqtadir sent Ashot II a crown and royal vestments and recognized him as Shahinshah of Armenia, that is, “the King of Kings”.